Ethosuximide-associated Aplastic Anemia Likely Due to Drug-induced Lupus Erythematosus: A Case Report With Immunologic Insights

Ethosuximide-associated aplastic anemia (AA) is a rare idiosyncratic disorder with unclear etiology. We report a 17-year-old female with absence seizures on ethosuximide, who was incidentally found to have pancytopenia and a markedly hypocellular marrow (<5% cellularity) with lupus erythematosus (LE) cells. The presence of antinuclear and anti-histone antibodies supported a diagnosis of AA secondary to drug-induced lupus erythematosus. Ethosuximide was discontinued, and prednisone started with marked blood count recovery. Our case is the first to elucidate the particular lupus erythematosus association, as evidenced by the combination of immunologic serology, marrow aplasia, and the presence of marrow LE cells.